State... That isn't real advice. You think ALL INTPs play world of warcraft? REALLY? :rolli: Go try and hit on one with your own advice, see what happens. That's how you verify as to whether you are giving good advice or not.
Cracking the INTP-
Make friends with them. Establish some trust with them. Have interesting conversations with them, make them think. Be open minded, prove that you aren't a narrow minded idiot human being. Relate to their humor and participate. EDIT: Relate to their perspective, relate and take interest in their interests.
As for hitting on an INTP (from my experience, female) start with perhaps some flirty activity or chat and build from there.
If you establish this trust with them then they will like you as a friend, they are open minded and accepting people. Believe me, you will know if they don't like you. With my experience INXX people like to make friends first.
Other than that it's reliant on the person. Do they like you? Do you like them? Do they appear interested? Ask these basic relationship questions to yourself along with all of those other things I mentioned and you should be ok. I'm open to being told I'm wrong, so feel free if I am. Most of my experience is from females, so if it's inaccurate to males then that may explain it.